Question

Miss Chen organized her students’ quarter grades in the box-and-whisker plot below. Use the plot to answer the following questions.


What is the interquartile range of the quarter grades in Miss Chen’s class?
a. 31
b. 96
c. 11
d. 65

Answer 1

The correct answer is c)11.

The interquartile range is found by subtracting the upper quartile and lower quartile.  From the plot, we see the UQ is 90 and the LQ is 79 (they form the edges of the box).

90 - 79 = 11